This application is related to Japanese Patent Application No. Hei 11(1999)-065445 filed on Mar. 11, 1999, whose priority is claimed under 35 USC xc2xa7 119, the disclosure of which is incorporated by reference in its entirety.
1. Field of the Invention
The present invention relates to a translator, a translating method and a recording medium having a translating program recorded thereon which serve to extract a derivative including a prefix and a suffix and a word base that has not been registered in a word dictionary, thereby generating a translated word.
2. Description of the Related Art
In recent years, a translator such as an English-to-Japanese translator has been increasingly required and has been variously developed. In a conventional translator, for example, a source language (an original language) is input to storage means through input means-such as a keyboard and the input source language is translated into a target language (an object language) through translating means by utilizing a table in which a word dictionary, syntax rules and tree structure conversion rules are stored.
In this case, the original language which has not been registered in the word dictionary is usually processed as an unknown word. Therefore, it has been necessary to translate the unknown word by referring to other dictionaries and the like later.
However, the unknown word includes a derivative having a prefix or a suffix added to a known word (word base), and the word base constituting the derivative is registered in the word dictionary. If the prefix or the suffix included in the derivative can be analyzed, the meaning of the derivative can also be presumed based on the meaning of the word base and that of the prefix or the suffix.
For example, Japanese Unexamined Patent Publication No. Sho 63(1988)-109572 has proposed a derivative processing method in which a word dictionary and an affix dictionary are provided, it is decided whether or not an unknown word detected in an input text is a derivative obtained by linking a prefix or a suffix to a known word, and grammatical properties having a grammar information for generating an object (a translated word), semantic properties, translated words or the like for the unknown word recognized as the derivative are particularly presumed according to the conditions, resulting in an enhancement in the certainty of the results of analysis and translation.
However, the derivative processing method described in the above-mentioned Japanese Unexamined Patent Publication No. Sho 63(1988)-109572 has a problem in that a proper translated word cannot be obtained depending on the structure of the derivative as will be described below.
(1) A derivative including a plurality of affixes has no function of accurately extracting the affix. Therefore, when a word of xe2x80x9cexportablexe2x80x9d is translated, for example, it might be recognized as a derivative having a prefix of xe2x80x9cexxe2x80x9d and a known word of xe2x80x9cportablexe2x80x9d and might be translated by mistakexe2x80x9d.
However, the English word of xe2x80x9cexportablexe2x80x9d should be recognized as a derivative having a known word of xe2x80x9cexportxe2x80x9d and a suffix of xe2x80x9cablexe2x80x9d.
(2) In the case where the notation of a word base includes a part of the notation of a suffix, there is no function of accurately extracting the word base. Therefore, when a word of xe2x80x9cnoterxe2x80x9d is translated, it might be recognized as a derivative having a word of xe2x80x9cnotxe2x80x9d and a suffix of xe2x80x9cerxe2x80x9d However, the English word of xe2x80x9cnoterxe2x80x9d should be recognized as a derivative having a known word of xe2x80x9cnotexe2x80x9d and a suffix of xe2x80x9cerxe2x80x9d.
(3) The translated word of the suffix is uniformly registered. Therefore, if the translated word of a prefix of xe2x80x9cnonxe2x80x9d is determined as xe2x80x9cxe2x80x9d, for example, an English word of xe2x80x9cnonremunerativexe2x80x9d is recognized as a derivative having a prefix of xe2x80x9cnon ()xe2x80x9d and a known word of xe2x80x9cremunerative ()xe2x80x9d and a translated word thereof is defined as xe2x80x9cxe2x80x9d obtained by linking the translated word of xe2x80x9cnon ()xe2x80x9d. This translated word is unnatural as Japanese.
Based on the translation form of a word base, the translated word of xe2x80x9cnonxe2x80x9d is obtained by replacing xe2x80x9cthere is ()xe2x80x9d with xe2x80x9cthere is not ()xe2x80x9d. Consequently, the English word of xe2x80x9cnonremunerativexe2x80x9d should be translated as xe2x80x9cxe2x80x9d to obtain a natural Japanese translated word.
In consideration of the above-mentioned circumstances, it is an object of the present invention to provide a translator, a translating method and a recording medium having a translating program recorded thereon in which when a derivative having a plurality of combinations of an affix and a word base is recognized from an input original language that has not been registered in a word dictionary, an accurate derivative having an original affix and word base can be extracted to generate a natural translated word.
The present invention provides a translator comprising a word dictionary, an affix dictionary, an input section for inputting an original language to be a first language, a converting section for referring to the word dictionary, thereby converting the input original language into a translated word to be a second language, a recognizing section for referring to the word dictionary and the affix dictionary, thereby recognizing a derivative having an affix and a word base from the input original language which cannot be converted into the translated word by the converting section, a derivative translation generating section for linking a translated word corresponding to the affix of the recognized derivative to a translated word corresponding to the word base, thereby generating a translated word of one derivative, and an affix determining section for determining one affix based on an affix processing condition given from a language characteristic information when a derivative including a plurality of affixes is recognized by the recognizing section, wherein the derivative translation generating section generates a translated word of a derivative having the affix determined by the affix determining section and a word base corresponding thereto.
According to the present invention, there is provided the means for determining an affix based on the affix processing conditions given from the language characteristic information of a source language. Consequently, even if a derivative has a plurality of combinations of an affix and a word base for an input text which has not been registered in the word dictionary, an optimal affix can be determined and an accurate derivative can be recognized based on a word base corresponding to the optimal affix. Thus, a natural translated word can be generated.
According to the present invention, an affix is determined based on the language characteristic information of a source language when an unknown word in a text is to be morphologically analyzed. Consequently, also in the case where there are a plurality of combinations of an affix and a word base for the unknown word in the text, it is possible to select the optimal combination of an affix and a word base with a great possibility. Consequently, the text can be analyzed more accurately.
These objects as well as other objects, features and advantages of the invention will become more apparent to those skilled in the art from the following description with reference to the accompanying drawings.